Gyratory sifter.



' movement, to prevent one end becoming JOHN M. CASE, OF LOUISVILLE, KENTUCKY.

GYRATORY SIFTER.

Specification of Letters Patent.

Patented May 7, 1907.

Application filed January 8, 1906. Serial No 295,138.

To all whom, it may concern:

Be it known that I, JOHN M. CAsE, a citizen of the United States, and residing in Louisville, county of Jefferson, State of Kentucky, have invented certain new and useful Improvements in Gyratory Sifters, of which the following is a specification.

This invention relates to gyratory sifters.

An object of the invention is to improve the mechanism for producing a parallel motion, sidewise of the sieve box, that is, mechanism by which both ends of the box are caused to make the same amount of heavier than the other, owing to a greater amount of material accumulating at the heavy end. IVhen this action once starts in a sieve it does not improve but becomes worse, causing the material to move in the wrong direction and often piling up at the head of the machine, producing choke-ups: or causing the entire product to move to one side of the sieves where it travels in a thick stream leaving the balance of the cloth bare.

A further object of my invention is to provide an improved means for cleaning the sieve cloth without producing any wearing action thereon. Other and still further objects will appear in the following description and will be more particularly pointed out in the appended claims.

In the drawings: Figure 1 is a top plan view of my sifter showing the means for causing the box to move in parallel paths. Fig. 2 is a side elevation part y in section. Fig. 3 is a top plan view of one of the sieves of my sifter. Fig. 4' is a vertical longitudinal section through a sieve. Fig. 5 is a transverse vertical section through a sieve. Figs. 6 and 7 are respectively a side elevation and a top plan of one of the cleaning bars. Fig. 8 is another embodiment of the means for causing the box to move in parallel paths.

Referring more particularly to the drawings, 1 indicates the base frame, 2 the sieve box, 3 the standards on which the box gyrates, and 4 the mechanism for producing the gyratory motion.

Pivoted to the bottom of the box 2 near each end and to one side thereof, is a pair of swinging links 5 which extend horizontally beneath the box to the opposite side where they are pivoted to a pair of levers 6. The levers 6 extend toward one another andare journaled on bearings 7 on a support to be i hereinafter more fully described, and are connected by means of two extensions 8 having intermeshing racks 9, thus causing both levers to have the same extent of movement and in the same direction, and, as these levers are connected with opposite ends of the sieve box, it is impossible for one end to have a greater movement than the other. I have shown in Fig. 8 another means for causing the levers to move the ends of the box at the same speed. In this embodiment the levers 6 are provided with lateral extensions 8 disposed in opposite directions and connected by a link 9 The support upon which the bearings 7 are mounted is extensible to permit the bearings to be adjusted vertically and the horizontal links 5 to be maintained in perfect horizontal positions. This extension is accomplished by providing the foot member 10 with a vertical slot 11, the upper member 12, which carries the bearings 7, being adjustably clamped thereto by a bolt 13. The foot member is secured to the base frame 1 in any suitable manner.

Within the box 2 the sieves 14 are mounted in the usual manner. These sieves have a rectangular frame 15 and are covered with a bolting cloth 16, the bolting cloth being supported between the ends of the frame by transverse flexible strips 17 secured at their ends to the side bars of the frame and about one inch wide and an eighth of an inch thick. The cross bars 18 of the frame are spaced below the top of the frame about one fourth an inch below the upper face of the sieve, the cross bars being located between the strips 17 and not beneath the same. Alongitudinal bar 19 extends the length of the frame and engages with the bottom of the flexible supporting strips near their centers.

Upon each side of the longitudinal bar 19 and between the flexible strips 17 and the cross bars 18 are located flexible bars 20, which are shorter than the inside length of the frame and are free to move both longitudinally and transversely of the bolting cloth. The flexible bars may be made of any material but EI prefer to use hoop steel iron #20 gage and about one and one fourth inches in width. To produce a stroke below the line of motion of the bar at the ends thereof, I bend the said ends downwardly at 21, thus producing an upward spring between the ends throughout the entire length, and this I out of the ends of the frame due to contact by the ends of the flexible bars, I rivet or otherwise secure to the depending portions 21, a piece of heavy leather 22 to produce a ,cushion and at the ends of the frame I secure curved pieces of hoop iron 23 which are mounted to prevent the ends of the flexible bars entering the corners of the frame.

I Having thus described my invention what I claim and desire to secure by Letters Patent is:

1. The combination with the gyratory sieve box, of a I pair of parallel horizontal links pivoted to the box, a pair of levers pivotally connected at one end to the free ends of the links, extending toward each other and pivoted near their other ends, and connection between the adjacent or inner ends of the levers causing the outer ends to move simultaneously in the same direction.

2. The combination with the gyratory sieve box, of a pair of horizontal links connected to the box near each end thereof and upon the same side of the box, and extending to the opposite side of the box, a pair of piv, oted levers connected to the free ends of the links and extending toward one another, connection between the adjacent ends of the levers, and an extensible support upon which the pivoted levers are mounted.

3. The combination with the frame, of flexible supports secured at their ends to the side bars of the frame, a bolting cloth secured to the frame and resting loosely on the flexible supports, and means engaging the flexible supports to clean the'cloth.

4. The combination with the frame and a bolting cloth secured thereto, of transverse bars arranged below the bolting cloth in spaced relation to said cloth, and a flexible bar arranged longitudinally of the bolting cloth and between the transverse bars and the bolting cloth, and capable of moving freely longitudinally and transversely of the clot 1.

5. The combination with the frame anda bars arranged below the bolting cloth in spaced relation to said cloth, a flexible bar arranged longitudinally of the bolting cloth and between the transverse bars and the bolting cloth and capable of moving freel longitudinally and transversely of the cloth, and cushions at the ends of the bar.

7. The combination with the sieve cloth, of the transverse flexible strips beneath the cloth, and a longitudinal flexible bar mounted to move transversely and longitudinally to engage with the strips during a gyratory motion of the sieve cloth.

8. The combination with the screen frame, a cloth covering the same, a series of transverse flexible strips beneath the cloth, a longitudinal bar beneath the strips, and means supporting the bar and permitting a longitudinal and transverse movement thereof.

9. The combination with the screen frame, a cloth covering the same, a series of transverse flexible strips beneath the cloth, a lon gitudinal bar beneath the strips, and cross bars on which the bar is freely movable longitudinally and transversely.

10. The combination with the shifting frame and a bolting cloth secured thereto, of

a flexible bar freely movable beneath the cloth and having its ends deflected downwardly away from the cloth to engage the frame and cause the bar to bend upwardly between its ends and means for supporting the bar beneath the cloth.

The foregoing specification signed at Louisville, Kentucky this twenty sixth (26th) day of December, 1905.

- JOHN M. CASE. 

